Ryan Photographic - Gobiidae - Gobies

Family Gobiidae - gobies

FishBase lists 212 genera and 1875 species in this enormously important but often over-looked family. Gobies are ubiquitous - they are found in desert pools in Australia, freshwaters of the Pacific Islands and in all the world's oceans. If we accept the figure of 28,000 fish species then approximately one in every 14 fish species is a goby.

Gobies are fond of associations. Ghostgobies and spongegobies are intimately associated with their hosts - going so far as to abuse this hospitality by laying their eggs on them. A whole suite of gobies share a burrow with prawns. These prawn or shrimp gobies act as sentinels for the shrimp. Their keen eyesight spots potential predators at a distance and the goby responds by backing (or diving) into the burrow. The nearly-blind shrimps normally keep an antenna on their watch goby and immediately take refuge when their pusillanimous lodger heads for shelter.

Gobies are important in Pacific Island streams and several species lay eggs which hatch and drift downstream to the ocean. Depending on species there may be a mass migration of the youngsters back up river a few weeks or months later. These goby populations can reach high densities. Because they are algal grazers they are the primary consumers and have more energy available to them than if they were predators. I wrote a paper about this and other factors entitled "The success of the Gobiidae in tropical Pacific insular streams".

In the Caribbean neon gobies work as fish cleaners. Unlike cleaner wrasse in the Pacific where only one or two individuals are involved it isn't uncommon to see a dozen neon gobies cleaning their patient.

Gobies don't always stay where they should. The round goby, Neogobius melanstomus, arrived in the Great Lakes of North America in 1990, presumably in ballast water of ships traveling from its native Black and Caspian Seas.